| From | Kamal Mostafa <> | Subject | [PATCH 4.2.y-ckt 084/218] bcache: fix cache_set_flush() NULL pointer dereference on OOM | Date | Thu, 31 Mar 2016 13:14:57 -0700 |
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4.2.8-ckt7 -stable review patch. If anyone has any objections, please let me know.
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From: Eric Wheeler <git@linux.ewheeler.net>
commit f8b11260a445169989d01df75d35af0f56178f95 upstream.
When bch_cache_set_alloc() fails to kzalloc the cache_set, the asyncronous closure handling tries to dereference a cache_set that hadn't yet been allocated inside of cache_set_flush() which is called by __cache_set_unregister() during cleanup. This appears to happen only during an OOM condition on bcache_register.
Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/md/bcache/super.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index d7ce93e..eff6144 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1398,6 +1398,9 @@ static void cache_set_flush(struct closure *cl) struct btree *b; unsigned i; + if (!c) + closure_return(cl); + bch_cache_accounting_destroy(&c->accounting); kobject_put(&c->internal); -- 2.7.4
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